Crossed-microwave-beam air ionization laboratory experiments

Conference · Mon Jan 01 00:00:00 EST 1990

OSTI ID:7003334

Armstrong, W T; Karl, R; Kelly, M; Roussel-Dupre, R; Buchwald, M; Sutherland, C D; Zinn, J ^[1]; Alvarez, R; Bolton, P; Sieger, G; Patterson, W ^[2]; Hunton, D; Trzcinski, E ^[3]; Eckstrom, D; Stalder, K ^[4]; Testerman, L; Tunnell, T; Blain,

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1. Los Alamos National Lab., NM (USA)
2. Lawrence Livermore National Lab., CA (USA)
3. Air Force Geophysics Lab., Hanscom AFB, MA (USA)
4. SRI International, Menlo Park, CA (USA)

Detailed laboratory measurements and theoretical modeling relevant to the production, geometrical description and decay of microwave-induced air ionization for an upper atmospheric RF reflecting layer are reported. It is found that breakdown thresholds are adequately predicted by fluid models and simplified scaling models with refinement by kinetic models being important at lower pressures. Repetitive pulse sustainment has been demonstrated to be straightforward with a commensurate reduction in sustainment power levels. However, establishment of a convenient breakdown geometry for specular RF reflections, other than a single layer in a crossed beam geometry, was not obtained. Detailed density decay measurements qualitatively support estimates of decay times and indicate ionization dwell times of tens of milliseconds. Chemistry studies indicate three N{sub x}O{sub x} species will be produced. Further study of these collateral reactions is required to establish whether adverse atmospheric consequences can result. However, large N{sub x}O{sub x} production does not appear as a concern for relatively small, low repetition rate, proof of concept atmospheric experiments. A realizable proof of concept experiment is found with simple optimization criteria which is corroborated by laboratory measurements and theoretical simulations. Tail-erosion appears as a potentially severe limitation in atmospheric experiments beyond the proof of concept level, suggesting use of multiple-beam systems. 20 refs., 18 figs.

• Research Organization: Los Alamos National Laboratory (LANL), Los Alamos, NM (United States)
• Sponsoring Organization: USDOD
• DOE Contract Number: W-7405-ENG-36
• OSTI ID: 7003334
• Report Number(s): LA-UR-90-1787; CONF-9005208-1; ON: DE90012056
• Resource Relation: Conference: AGARD Spring 1990, electromagnetic wave propagation panel symposium, (Norway), May 1990
• Country of Publication: United States
• Language: English

Related Subjects

71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
47 OTHER INSTRUMENTATION
EARTH ATMOSPHERE
IONIZATION
RADIOWAVE RADIATION
REFLECTION
COMMUNICATIONS
MESOSPHERE
MICROWAVE RADIATION
RF SYSTEMS
STRATOSPHERE
ELECTROMAGNETIC RADIATION
RADIATIONS
640200* - Atmospheric Physics
440800 - Miscellaneous Instrumentation- (1990-)